As solar collectors may be constructed in remote areas, to which access is often difficult, means have been sought of buidling a support structure which is easily transported and which can be assembled on site, and with this in mind, it has already been proposed to build a support structure employing a technique which is well known for scaffolding, i.e., taking the form of a set of bars linked by assembly nodes. For example, a structure of this type is described in European Patant application No. 0,025,320. In such a system, the concave dish consists of a triangular lattice which is developed around a central node positioned on the axis. According to the shape to be given to the dish, various assemblies of geometrical shapes may be envisaged, but it is advantageous for the assemblies to be constructed on a basis of triangles; it is thus possible to make a reflecting surface from triangular facets fixed to the bars.
Such a concave triangular lattice has insufficient strength of its own for the use being considered, and for this reason it is combined with a second set of stiffening bars which is also developed from a central node, and which may constitute, in several planes passing through the axis, rigid half-trusses extending radially from a common central strut consisting of a column which is positioned on the axis and which carries at its ends central assembly nodes for the two sets of bars.
It is this type of system which is described in European Patent application No. 0,025,320, mentioned above, but such a system presents a disadvantage in that the stiffening bars are positioned inside the dish which inevitably results in the reduction of the light collected due to the shadows of these bars cast on the reflecting surface. In addition, it is not easy to adapt a support system to such a structure which is capable of orientating the dish in all directions from a central pivot forming a universal articulation.